Robot To Wash Solar Panels Among Winning Student Inventions

Students took home $200,000 in prizes for green ideas at an awards ceremony recently held at California Institute of Technology for a Department of Energy competition.

The three winning entrepreneurs won with ideas for robots for cleaning solar panels, developing energy from waste water treatment, and 20% more efficient solar cells. Stanford Nitrogen Group, Greenbotics and Xite Solar shared the prize money. The western region’s three winners in the DOE’s National Clean Energy Business Plan Competition (NCEBPC) were chosen by a top panel of judges including top Silicon Valley green innovation hunters Kleiner Perkins and Khosla Ventures.

Next these three regional winners will join winning teams from five other regions across the country, who will compete in the nation’s capital in June. All told, 83 applicants from 34 universities across twelve states submitted inventions ranging from new battery materials for portable electronic devices to net energy+ home kits, hydroponic farms and telephone apps for tracking energy use in the home.

image via Greenbotics

The most interesting of the three ideas, to me, is the remotely controlled Greenbotics robotic cleaner from CalTech and UCLA.

Given the enormous expansion coming in solar over the next few years, I think the Greenbotics solar panel cleaner is a real winner. This market currently represents 368 MW of installed capacity across 18 plants, and is expected to grow significantly to 20GW of installed capacity across 135 plants by 2015.

Soft rotating brushes and squeegies alternate within a very lightweight robotic device that is sized to cover two typical sized utility-scale panels vertically at a time, while moving sideways along the rows. Only a small amount of water is used, since the squeegie removes the used water, leaving a clean panel. It’s very light, incorporating materials and fabrication techniques of lightweight aircraft construction.

Two operators can easily place the lightweight robot at the start of a typical ground-mounted double row of panels, then a computer coordinates the robot and relays the system information to an operator who monitors the cleaning progress and issues commands.

Their robot cleaner can improve electrical generation in utility-scale solar projects by up to 15 percent, the inventors claim – likely true of any cleaning system. The students do not offer any comparison between their technology and whatever technology solar developers now use. How much less water can the robot use and still get the panels clean? Since all developers of utility-scale solar approved in California must detail for regulators exactly how they plan to clean the panels, and exactly how much water that will require, in precise acre feet per year, it will be that technology that will be the competition for this idea, not the option of leaving panels unwashed.

Susan Kraemer enjoys writing to publicize the many great solutions for climate change that we can find if we just put our minds to it. She covers renewable policy and clean energy for CleanTechnica and GreenProphet and green building at HomeDesignFind. She recently moved home to Waiheke Island where her writing is now powered by the 80% renewable electricity that powers New Zealand.